The word 保险箱 is formed by combining three meaningful characters: 保 (bǎo, meaning "to protect"), 险 (xiǎn, meaning "danger" or "risk"), and 箱 (xiāng, meaning "box" or "chest"). The first two characters together, 保险, form the concept of "insurance" or "safeguarding", which is then directly attached to 箱 ("box") to create a new, compound idea. Thus, the entire term visually and conceptually builds from "protect" + "danger" + "box" to logically arrive at the meaning of a "safe" or "strongbox", literally a box for protecting things from danger.